mysql安装
mysql8.0.27 免安装教程连接：安装教程连接
现象
1. mysql本地启动正常
C:\Users\youc>mysql -u root -p
Enter password: ********
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.27 MySQL Community Server - GPL
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
2. 数据库远程连接失败
错误代码：
java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up
数据库链接：jdbc:mysql://192.168.53.30:3306/test?characterEncoding=utf8&connectTimeout=1000&socketTimeout=30000&autoReconnect=true&useUnicode=true&useSSL=false&useTimezone=true&serverTimezone=Asia/Shanghai
备注：192.168.53.30:3306 本机地址：端口号 / 数据库名？连接配置
错误排查
- 开启远程连接
##开启root用户远程访问权限
CREATE USER 'root'@'%' IDENTIFIED BY '你的密码';
##如果报错,执行下一句
DROP USER 'root'@'%'
GRANT ALL ON *.* TO 'root'@'%';
ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY '你的密码';
FLUSH PRIVILEGES;
- 检查是否开启远程连接
mysql> use mysql;
Database changed
## 如果结果中存在 host：% user：root 结果，可以肯定远程连接开启了
mysql> select host,user,password from user;
+--------------+------+-------------------------------------------+
| host | user | password |
+--------------+------+-------------------------------------------+
| % | root | *A731AEBFB621E354CD41BAF207D884A609E81F5E |
| 192.168.1.1 | root | *A731AEBFB621E354CD41BAF207D884A609E81F5E |
+--------------+------+-------------------------------------------+
2 rows in set (0.00 sec)
-
检查防火墙，最坑的window设置，就是这个小问题，困扰了我一整天
操作：关闭 window防火墙，直接关了，不要想着只开发一个端口，直接关掉，不要幻想，关掉，重要的事情说三遍！！！
附端口查询命令#查看端口
firewall-cmd --list-ports
#开放3306端口
firewall-cmd --zone=public --add-port=3306/tcp --permanent
#重启防火墙
firewall-cmd --reload
- 使用上面的数据连接地址进行测试
